Time-resolved spectroscopy and photometry of an M dwarf flare star YZ
Canis Minoris with OISTER and TESS: Blue asymmetry in H$\alpha$ line during
the non-white light flare
In this paper, we present the results from spectroscopic and photometric
observations of the M-type flare star YZ CMi in the framework of the Optical
and Infrared Synergetic Telescopes for Education and Research (OISTER)
collaborations during the Transiting Exoplanet Survey Satellite (TESS)
observation period. We detected 145 white-light flares from the TESS light
curve and 4 H$\alpha$ flares from the OISTER observations performed between
2019-01-16 and 2019-01-18. Among them, 3 H$\alpha$ flares were associated with
white-light flares. However, one of them did not show clear brightening in
continuum; during this flare, the H$\alpha$ line exhibited blue-asymmetry which
has lasted for $60$ min. The line of sight velocity of the blue-shifted
component is $-80$ - $-100$ km s$^-1$. This suggests that there can be upward
flows of chromospheric cool plasma even without detectable red/NIR continuum
brightening. By assuming that the blue-asymmetry in H$\alpha$ line was caused
by a prominence eruption on YZ CMi, we estimated the mass and kinetic energy of
the upward-moving material to be $10^16$ - $10^18$ g and $10^29.5$ -
$10^31.5$ erg, respectively. The estimated mass is comparable to expectations
from the empirical relation between the flare X-ray energy and mass of
upward-moving material for stellar flares and solar CMEs. In contrast, the
estimated kinetic energy for the non-white-light flare on YZ CMi is roughly $2$
orders of magnitude smaller than that expected from the relation between flare
X-ray energy and kinetic energy for solar CMEs. This could be understood by the
difference in the velocity between CMEs and prominence eruptions.
Description
Time-resolved spectroscopy and photometry of an M dwarf flare star YZ Canis Minoris with OISTER and TESS: Blue asymmetry in H$\alpha$ line during the non-white light flare
%0 Generic
%1 maehara2020timeresolved
%A Maehara, Hiroyuki
%A Notsu, Yuta
%A Namekata, Kousuke
%A Honda, Satoshi
%A Kowalski, Adam F.
%A Katoh, Noriyuki
%A Ohshima, Tomohito
%A Iida, Kota
%A Oeda, Motoki
%A Murata, Katsuhiro L.
%A Yamanaka, Masayuki
%A Takagi, Kengo
%A Sasada, Mahito
%A Akitaya, Hiroshi
%A Ikuta, Kai
%A Okamoto, Soshi
%A Nogami, Daisaku
%A Shibata, Kazunari
%D 2020
%K activity mdwarf
%T Time-resolved spectroscopy and photometry of an M dwarf flare star YZ
Canis Minoris with OISTER and TESS: Blue asymmetry in H$\alpha$ line during
the non-white light flare
%U http://arxiv.org/abs/2009.14412
%X In this paper, we present the results from spectroscopic and photometric
observations of the M-type flare star YZ CMi in the framework of the Optical
and Infrared Synergetic Telescopes for Education and Research (OISTER)
collaborations during the Transiting Exoplanet Survey Satellite (TESS)
observation period. We detected 145 white-light flares from the TESS light
curve and 4 H$\alpha$ flares from the OISTER observations performed between
2019-01-16 and 2019-01-18. Among them, 3 H$\alpha$ flares were associated with
white-light flares. However, one of them did not show clear brightening in
continuum; during this flare, the H$\alpha$ line exhibited blue-asymmetry which
has lasted for $60$ min. The line of sight velocity of the blue-shifted
component is $-80$ - $-100$ km s$^-1$. This suggests that there can be upward
flows of chromospheric cool plasma even without detectable red/NIR continuum
brightening. By assuming that the blue-asymmetry in H$\alpha$ line was caused
by a prominence eruption on YZ CMi, we estimated the mass and kinetic energy of
the upward-moving material to be $10^16$ - $10^18$ g and $10^29.5$ -
$10^31.5$ erg, respectively. The estimated mass is comparable to expectations
from the empirical relation between the flare X-ray energy and mass of
upward-moving material for stellar flares and solar CMEs. In contrast, the
estimated kinetic energy for the non-white-light flare on YZ CMi is roughly $2$
orders of magnitude smaller than that expected from the relation between flare
X-ray energy and kinetic energy for solar CMEs. This could be understood by the
difference in the velocity between CMEs and prominence eruptions.
@misc{maehara2020timeresolved,
abstract = {In this paper, we present the results from spectroscopic and photometric
observations of the M-type flare star YZ CMi in the framework of the Optical
and Infrared Synergetic Telescopes for Education and Research (OISTER)
collaborations during the Transiting Exoplanet Survey Satellite (TESS)
observation period. We detected 145 white-light flares from the TESS light
curve and 4 H$\alpha$ flares from the OISTER observations performed between
2019-01-16 and 2019-01-18. Among them, 3 H$\alpha$ flares were associated with
white-light flares. However, one of them did not show clear brightening in
continuum; during this flare, the H$\alpha$ line exhibited blue-asymmetry which
has lasted for $\sim 60$ min. The line of sight velocity of the blue-shifted
component is $-80$ - $-100$ km s$^{-1}$. This suggests that there can be upward
flows of chromospheric cool plasma even without detectable red/NIR continuum
brightening. By assuming that the blue-asymmetry in H$\alpha$ line was caused
by a prominence eruption on YZ CMi, we estimated the mass and kinetic energy of
the upward-moving material to be $10^{16}$ - $10^{18}$ g and $10^{29.5}$ -
$10^{31.5}$ erg, respectively. The estimated mass is comparable to expectations
from the empirical relation between the flare X-ray energy and mass of
upward-moving material for stellar flares and solar CMEs. In contrast, the
estimated kinetic energy for the non-white-light flare on YZ CMi is roughly $2$
orders of magnitude smaller than that expected from the relation between flare
X-ray energy and kinetic energy for solar CMEs. This could be understood by the
difference in the velocity between CMEs and prominence eruptions.},
added-at = {2020-10-01T16:20:22.000+0200},
author = {Maehara, Hiroyuki and Notsu, Yuta and Namekata, Kousuke and Honda, Satoshi and Kowalski, Adam F. and Katoh, Noriyuki and Ohshima, Tomohito and Iida, Kota and Oeda, Motoki and Murata, Katsuhiro L. and Yamanaka, Masayuki and Takagi, Kengo and Sasada, Mahito and Akitaya, Hiroshi and Ikuta, Kai and Okamoto, Soshi and Nogami, Daisaku and Shibata, Kazunari},
biburl = {https://www.bibsonomy.org/bibtex/2984338f032c6c17bcc6a24f52945de07/superjenwinters},
description = {Time-resolved spectroscopy and photometry of an M dwarf flare star YZ Canis Minoris with OISTER and TESS: Blue asymmetry in H$\alpha$ line during the non-white light flare},
interhash = {92dd4176db3c7754226107d444cc7dd7},
intrahash = {984338f032c6c17bcc6a24f52945de07},
keywords = {activity mdwarf},
note = {cite arxiv:2009.14412Comment: 39 pages, 15 figures, supplementary table (CSV format); accepted for publication in PASJ},
timestamp = {2020-10-01T16:20:22.000+0200},
title = {Time-resolved spectroscopy and photometry of an M dwarf flare star YZ
Canis Minoris with OISTER and TESS: Blue asymmetry in H$\alpha$ line during
the non-white light flare},
url = {http://arxiv.org/abs/2009.14412},
year = 2020
}